Ethylene diurea Wikipedia
Ethylene diurea (EDU) is a chemical compound with the formula C4H10N4O2. It has been analyzed by several groups to determine whether it is a successful antiozonant. If so, this substance would help crops by preventing the harmful effects on crops by ozone. In an experiment run in 2002 by a group called Alberta Environment (now known as Alberta Environment and Sustainable Resource Development, they determined that EDU did one of two things. The substance either prevented the harmful effects of ozone or it stimulated plant growth.
In an experiment run this year, a group at the Institute of Plant Protection examined trees that were exposed to ambient ozone and trees that were treated with EDU. The study determined that trees treated with EDU were significantly healthier in both leaf longevity and water use efficiency. This further shows this compounds helps defend plants from the harmful effects of ozone.
In another experiment in Spain in 1999, a group working at Centre de Recerca Ecològica i Aplicacions Forestals found that the effectiveness of EDU was dependent upon many different environmental factors. They took data at three different stations, each with different meteorological conditions and ozone concentrations. They found that EDU helped protect against ozone effects but with different levels.